The 4.5/Curve version also appears to work for the Pearl 8100 and 8800 series, so if you own one of these BlackBerry devices and want to try BBM 5.0 make sure this is the one you download and not any other version. It is also important to remember that you need a minimum OS of 4.5.0.131, but having the latest OS definitely helps. You can find the latest OS for your Blackberry here.